The present invention relates to a test station and a method for testing (micro) fluidic components, e.g. fluidic MEMS components or elements, e.g. micro pumps, micro valves, micro-reactors, etc. In particular, the present invention relates to an automatic test of fluidic components on wafer level.
To date, only a few MEMS (MEMS=micro electormechanical system) components, such as pressure sensors, gyroscopes and acceleration sensors can be found in large quantities on the world market. Fluidic MEMS components in silicon (Si), however, such as micro fluidic chips, micro dispensers, micro pumps and micro valves are only available in small quantities on the market. Limiting obstacles for entering the market with large quantities of such fluidic Si devices are the relatively high manufacturing costs.
As fluidic MEMS components are, up to now, in only relatively small quantities on the market, industrial producers of test devices are, so far, not willing to invest in device developments, as the quantities of devices to be possibly sold will hardly pay off investment costs. Hence, the development of MEMS test devices can still be considered as a niche application. In particular, a developed test station, beside a diaphragm testing unit for pressure sensor chips, an automatic fluidic MEMS device tester on wafer level, is not known on the market.
In the art, common characterization methods for fluidic components are known in the form of manual tests or based on half automatic test devices having specific test adapters for individual chips. Fluidic devices are, for example, first inserted into such specific adapters in an unpackaged manner and are then tested. However, in this case, the fluidic devices will subsequently have to be tested again after packaging, since chip assembly can include sources of error, which represents a disadvantage. Moreover, mounting the chip first into the package, wherein in many cases mounting is performed by means of an adhesive step firmly connecting the adhered chips with the package and hence preventing reuse of the package, and only then testing after chip packaging has some significant disadvantages and causes additional costs since chips that are defective or insufficient with regard to their specification are necessitated to be disposed of after the test, including the packaging. Therefore, the methods described above are disadvantageous in that they are very time-consuming and, hence, costly.
Thus, a general disadvantage of known methods for the characterization of fluidic MEMS components is that these methods are time-consuming and not cost-effective.